今天我们来分析一道关于保险利益的多项选择题。这道题要求我们识别关于保险利益的错误表述。保险利益是保险法中的核心原则，理解其正确含义对于学习保险法非常重要。让我们逐一分析每个选项。
首先分析选项A。选项A表述保险利益本质上是一种经济上的利益，即可以用金钱衡量的利益。这个表述是正确的。保险利益确实必须是经济利益，具有可以用货币计量的特征，与被保险人存在合法的利害关系。
接下来分析选项B。选项B表述人身保险的投保人在保险事故发生时对保险标的应当具有保险利益。这个表述是错误的。根据保险法规定，人身保险的投保人应当在保险合同订立时对被保险人具有保险利益，而不是在保险事故发生时。这是人身保险与财产保险在保险利益时效要求上的重要区别。
最后分析选项C和D。选项C表述财产保险的被保险人在保险合同订立时对保险标的应当具有保险利益，这个表述是正确的。选项D表述责任保险的投保人在保险合同订立时对保险标的应当具有保险利益，这个表述也是正确的。财产保险和责任保险都要求在合同订立时具有保险利益。
通过逐一分析，我们可以得出结论：选项A、C、D的表述都是正确的，只有选项B的表述是错误的。选项B错误地认为人身保险的投保人应在保险事故发生时具有保险利益，实际上应该是在保险合同订立时对被保险人具有保险利益。因此，本题的答案是B。
Let's analyze Option A in detail. Option A states that insurance interest is essentially an economic interest that can be measured in monetary terms. This statement is absolutely correct. Insurance interest must indeed be an economic interest with quantifiable monetary value. For example, property ownership can be valued at specific dollar amounts, and life insurance benefits represent measurable economic value. This economic nature is fundamental to preventing gambling in insurance contracts.
Now let's examine Option B. This option states that in life insurance, the policyholder should have insurance interest when the insured event occurs. This statement is incorrect. According to insurance law, life insurance requires the policyholder to have insurance interest in the insured person at the time of contract formation, not when the insured event occurs. This is a crucial distinction that prevents speculation and gambling in life insurance. For example, a parent can insure their child's life at contract formation, and the policy remains valid even if their relationship changes later.